1.  Connection of signal generator:

According to the grounding fault of the DC system, connect the signal generator to the positive and negative busbars and ground wires near the output end of the battery. It has been detected that there is a grounded branch but the circuit runs further away. To improve detection accuracy, the signal generator can be connected to the DC fuse outlet at the beginning of the branch closer to the fault area, or to the DC small busbar below the circuit. When testing, the signal generator should always be connected to the power supply end of the DC branch, while the fault detector and clamp meter should always be tested at the load end of the DC branch

2.  High detection efficiency, clamp the output line of one circuit of the meter clamp:

On the outlet lines of each fuse (bundled into one bundle) on the screen of the DC distribution panel, if the detection result is "non grounded", it indicates that there is no grounding fault in the circuit of the DC power supply. If the wire tie test result shows "grounding", clamp each circuit separately, and the detection method is the same as above. Assuming that after detecting a fault in the Nth feeder branch, if you want to further search for each branch below the feeder branch, you can continue to follow the above steps and use a clamp table to detect each branch. 1.  Detectable grounding resistance range

When the system voltage is 220V: 0-500K Ω

When the system voltage is 110V: 0-250K Ω

When the system voltage is 48V: 0-50K Ω

When the system voltage is 24V: 0-10K Ω

3; Detection signal power ≤ 0.2W (signal generator output power)

4; Resistance to ground distribution capacitance value:

Single branch capacitance to ground ≤ 8uF, total system capacitance to ground ≤ 100uF

5.  Applicable DC system voltage:

220V ± 10%, 110V ± 10%, 48V ± 10%, 24V ± 10%, or other voltage levels proposed by the user

3.  Further fault localization: After detecting the grounding branch, locate and detect the specific grounding fault point. Users can use the binary method to detect and locate the fault area during detection. After each detection, the fault area is located in a binary point selection method for the next detection, in order to quickly detect the specific grounding fault point; Assuming there is a grounding condition during the detection at A and no grounding condition during the detection at B, it can be determined that the grounding fault point is between A-B. At the same time, based on the direction of the feeder cable and the connection of the equipment, each feeder inlet of the faulty branch can be detected separately to identify the faulty branch and further locate the fault